1/**************************************************************************
2 *
3 * Copyright 2013 VMware, Inc.
4 * All Rights Reserved.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the
8 * "Software"), to deal in the Software without restriction, including
9 * without limitation the rights to use, copy, modify, merge, publish,
10 * distribute, sub license, and/or sell copies of the Software, and to
11 * permit persons to whom the Software is furnished to do so, subject to
12 * the following conditions:
13 *
14 * The above copyright notice and this permission notice (including the
15 * next paragraph) shall be included in all copies or substantial portions
16 * of the Software.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
19 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
20 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
21 * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
22 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
23 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
24 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
25 *
26 **************************************************************************/
27
28#include "draw_prim_assembler.h"
29
30#include "draw_fs.h"
31#include "draw_gs.h"
32#include "draw_tess.h"
33#include "util/u_debug.h"
34#include "util/u_memory.h"
35#include "util/u_prim.h"
36
37#include "pipe/p_defines.h"
38
39struct draw_assembler
40{
41   struct draw_context *draw;
42
43   struct draw_prim_info *output_prims;
44   struct draw_vertex_info *output_verts;
45
46   const struct draw_prim_info *input_prims;
47   const struct draw_vertex_info *input_verts;
48
49   boolean needs_primid;
50   int primid_slot;
51   unsigned primid;
52
53   unsigned num_prims;
54};
55
56
57static boolean
58needs_primid(const struct draw_context *draw)
59{
60   const struct draw_fragment_shader *fs = draw->fs.fragment_shader;
61   const struct draw_geometry_shader *gs = draw->gs.geometry_shader;
62   const struct draw_tess_eval_shader *tes = draw->tes.tess_eval_shader;
63   if (fs && fs->info.uses_primid) {
64      if (gs)
65         return !gs->info.uses_primid;
66      else if (tes)
67         return !tes->info.uses_primid;
68      else
69         return TRUE;
70   }
71   return FALSE;
72}
73
74boolean
75draw_prim_assembler_is_required(const struct draw_context *draw,
76                                const struct draw_prim_info *prim_info,
77                                const struct draw_vertex_info *vert_info)
78{
79   /* viewport index requires primitive boundaries to get correct vertex */
80   if (draw_current_shader_uses_viewport_index(draw))
81      return TRUE;
82   switch (prim_info->prim) {
83   case PIPE_PRIM_LINES_ADJACENCY:
84   case PIPE_PRIM_LINE_STRIP_ADJACENCY:
85   case PIPE_PRIM_TRIANGLES_ADJACENCY:
86   case PIPE_PRIM_TRIANGLE_STRIP_ADJACENCY:
87      return TRUE;
88   default:
89      return needs_primid(draw);
90   }
91}
92
93static void
94add_prim(struct draw_assembler *asmblr, unsigned length)
95{
96   struct draw_prim_info *output_prims = asmblr->output_prims;
97
98   output_prims->primitive_lengths = realloc(output_prims->primitive_lengths, sizeof(unsigned) * (output_prims->primitive_count + 1));
99   output_prims->primitive_lengths[output_prims->primitive_count] = length;
100   output_prims->primitive_count++;
101}
102
103/*
104 * Copy the vertex header along with its data from the current
105 * vertex buffer into a buffer holding vertices arranged
106 * into decomposed primitives (i.e. buffer without the
107 * adjacency vertices)
108 */
109static void
110copy_verts(struct draw_assembler *asmblr,
111           unsigned *indices, unsigned num_indices)
112{
113   unsigned i;
114
115   char *output = (char*)asmblr->output_verts->verts;
116   const char *input = (const char*)asmblr->input_verts->verts;
117
118   for (i = 0; i < num_indices; ++i) {
119      unsigned idx = indices[i];
120      unsigned output_offset =
121         asmblr->output_verts->count * asmblr->output_verts->stride;
122      unsigned input_offset = asmblr->input_verts->stride * idx;
123      memcpy(output + output_offset, input + input_offset,
124             asmblr->input_verts->vertex_size);
125      asmblr->output_verts->count += 1;
126   }
127   ++asmblr->num_prims;
128}
129
130
131static void
132inject_primid(struct draw_assembler *asmblr,
133              unsigned idx,
134              unsigned primid)
135{
136   int slot = asmblr->primid_slot;
137   char *input = (char*)asmblr->input_verts->verts;
138   unsigned input_offset = asmblr->input_verts->stride * idx;
139   struct vertex_header *v = (struct vertex_header*)(input + input_offset);
140
141   /* In case the backend doesn't care about it */
142   if (slot < 0) {
143      return;
144   }
145
146   memcpy(&v->data[slot][0], &primid, sizeof(primid));
147   memcpy(&v->data[slot][1], &primid, sizeof(primid));
148   memcpy(&v->data[slot][2], &primid, sizeof(primid));
149   memcpy(&v->data[slot][3], &primid, sizeof(primid));
150}
151
152
153static void
154prim_point(struct draw_assembler *asmblr,
155           unsigned idx)
156{
157   unsigned indices[1];
158
159   if (asmblr->needs_primid) {
160      inject_primid(asmblr, idx, asmblr->primid++);
161   }
162   indices[0] = idx;
163
164   add_prim(asmblr, 1);
165   copy_verts(asmblr, indices, 1);
166}
167
168static void
169prim_line(struct draw_assembler *asmblr,
170          unsigned i0, unsigned i1)
171{
172   unsigned indices[2];
173
174   if (asmblr->needs_primid) {
175      inject_primid(asmblr, i0, asmblr->primid);
176      inject_primid(asmblr, i1, asmblr->primid++);
177   }
178   indices[0] = i0;
179   indices[1] = i1;
180
181   add_prim(asmblr, 2);
182   copy_verts(asmblr, indices, 2);
183}
184
185static void
186prim_tri(struct draw_assembler *asmblr,
187         unsigned i0, unsigned i1, unsigned i2)
188{
189   unsigned indices[3];
190
191   if (asmblr->needs_primid) {
192      inject_primid(asmblr, i0, asmblr->primid);
193      inject_primid(asmblr, i1, asmblr->primid);
194      inject_primid(asmblr, i2, asmblr->primid++);
195   }
196   indices[0] = i0;
197   indices[1] = i1;
198   indices[2] = i2;
199
200   add_prim(asmblr, 3);
201   copy_verts(asmblr, indices, 3);
202}
203
204static void
205prim_quad(struct draw_assembler *asmblr,
206          unsigned i0, unsigned i1,
207          unsigned i2, unsigned i3)
208{
209   unsigned indices[4];
210
211   if (asmblr->needs_primid) {
212      inject_primid(asmblr, i0, asmblr->primid);
213      inject_primid(asmblr, i1, asmblr->primid);
214      inject_primid(asmblr, i2, asmblr->primid);
215      inject_primid(asmblr, i3, asmblr->primid++);
216   }
217   indices[0] = i0;
218   indices[1] = i1;
219   indices[2] = i2;
220   indices[3] = i3;
221
222   add_prim(asmblr, 4);
223   copy_verts(asmblr, indices, 4);
224}
225
226void
227draw_prim_assembler_prepare_outputs(struct draw_assembler *ia)
228{
229   struct draw_context *draw = ia->draw;
230   if (needs_primid(draw)) {
231      ia->primid_slot = draw_alloc_extra_vertex_attrib(
232         ia->draw, TGSI_SEMANTIC_PRIMID, 0);
233   } else {
234      ia->primid_slot = -1;
235   }
236}
237
238
239#define FUNC assembler_run_linear
240#define GET_ELT(idx) (start + (idx))
241#include "draw_prim_assembler_tmp.h"
242
243#define FUNC assembler_run_elts
244#define LOCAL_VARS   const ushort *elts = input_prims->elts;
245#define GET_ELT(idx) (elts[start + (idx)])
246#include "draw_prim_assembler_tmp.h"
247
248
249
250/*
251 * Primitive assembler breaks up adjacency primitives and assembles
252 * the base primitives they represent, e.g. vertices forming
253 * PIPE_PRIM_TRIANGLE_STRIP_ADJACENCY
254 * become vertices forming PIPE_PRIM_TRIANGLES
255 * This is needed because specification says that the adjacency
256 * primitives are only visible in the geometry shader so we need
257 * to get rid of them so that the rest of the pipeline can
258 * process the inputs.
259 */
260void
261draw_prim_assembler_run(struct draw_context *draw,
262                        const struct draw_prim_info *input_prims,
263                        const struct draw_vertex_info *input_verts,
264                        struct draw_prim_info *output_prims,
265                        struct draw_vertex_info *output_verts)
266{
267   struct draw_assembler *asmblr = draw->ia;
268   unsigned start, i;
269   unsigned assembled_prim = (input_prims->prim == PIPE_PRIM_QUADS ||
270                              input_prims->prim == PIPE_PRIM_QUAD_STRIP) ?
271      PIPE_PRIM_QUADS : u_reduced_prim(input_prims->prim);
272   unsigned max_primitives = u_decomposed_prims_for_vertices(
273      input_prims->prim, input_prims->count);
274   unsigned max_verts = u_vertices_per_prim(assembled_prim) * max_primitives;
275
276   asmblr->output_prims = output_prims;
277   asmblr->output_verts = output_verts;
278   asmblr->input_prims = input_prims;
279   asmblr->input_verts = input_verts;
280   asmblr->needs_primid = needs_primid(asmblr->draw);
281   asmblr->num_prims = 0;
282
283   output_prims->linear = TRUE;
284   output_prims->elts = NULL;
285   output_prims->start = 0;
286   output_prims->prim = assembled_prim;
287   output_prims->flags = 0x0;
288   output_prims->primitive_lengths = MALLOC(sizeof(unsigned));
289   output_prims->primitive_lengths[0] = 0;
290   output_prims->primitive_count = 1;
291
292   output_verts->vertex_size = input_verts->vertex_size;
293   output_verts->stride = input_verts->stride;
294   output_verts->verts = (struct vertex_header*)MALLOC(
295      input_verts->vertex_size * max_verts + DRAW_EXTRA_VERTICES_PADDING);
296   output_verts->count = 0;
297
298
299   for (start = i = 0; i < input_prims->primitive_count;
300        start += input_prims->primitive_lengths[i], i++)
301   {
302      unsigned count = input_prims->primitive_lengths[i];
303      if (input_prims->linear) {
304         assembler_run_linear(asmblr, input_prims, input_verts,
305                              start, count);
306      } else {
307         assembler_run_elts(asmblr, input_prims, input_verts,
308                            start, count);
309      }
310   }
311
312   output_prims->count = output_verts->count;
313}
314
315struct draw_assembler *
316draw_prim_assembler_create(struct draw_context *draw)
317{
318   struct draw_assembler *ia = CALLOC_STRUCT( draw_assembler );
319
320   ia->draw = draw;
321
322   return ia;
323}
324
325void
326draw_prim_assembler_destroy(struct draw_assembler *ia)
327{
328   FREE(ia);
329}
330
331
332/*
333 * Called at the very begin of the draw call with a new instance
334 * Used to reset state that should persist between primitive restart.
335 */
336void
337draw_prim_assembler_new_instance(struct draw_assembler *asmblr)
338{
339   asmblr->primid = 0;
340}
341